Planographic printing plate packing box and planographic printing plate packing structure

ABSTRACT

A planographic printing plate packing box that can help solve problems regarding cost reduction and management adaptability to multiple product types, and a planographic printing plate packing structure using the planographic printing plate packing box is to be provided without damaging the coat of the planographic printing plate. It is a is planographic printing plate packing box ( 30 ), formed by folding one or more corrugated fiberboards, is a packing box for fitting inside and packing a stacked object ( 20 ) of planographic printing plates. Side end portions of corrugated fiberboards are folded, and sides ( 44 T) and ( 48 T) at the tips of end side portions are so arranged as to oppose a side of the stacked object, and the sides of the tips of end side portions and the side of the stacked object are at least as close to parallelism as 30 degrees.

TECHNICAL FIELD

The present invention relates to a planographic printing plate packing box and a planographic printing plate packing structure, and more particularly to a planographic printing plate packing box suitable for application to a stacked object in a state in which planographic printing plates and slip-sheets are alternately stacked and a planographic printing plate packing structure using the planographic printing plate packing box.

BACKGROUND ART

Planographic printing plates, such as photosensitive printing plates and thermosensitive printing plates are extensively used in today's plate making processes (including electrotype processes) to simplify the automation of plate making steps. A planographic printing plate is usually fabricated by subjecting a base, such as a sheet-shaped or coil-shaped aluminum plate, to surface treatment such as sand roughing, anode oxidization, silicate treatment and/or other chemical formation either independently or in combination, after coating it with a photosensitive layer or a thermosensitive layer (hereinafter such layers will be collectively referred to as a “coat”, a coat face as an “image formation face” and an uncoated face as a “non-image formation face”) and dried, cutting the processed plate into the desired size.

The planographic printing plate above is subjected to plate making processes including exposure to light, development and gumming, and set onto a printing press. Then, ink is applied to the planographic printing plate set on the printing press, and its transfer results in printing of characters, images or the like on the paper surface.

Incidentally, when a plurality of planographic printing plates are to be stacked and carried, paper sheets known as slip-sheets may be placed in contact with the coats to protect the coats (image formation faces) applied to the bases. Especially for efficient handling of planographic printing plates, a plurality of planographic printing plates may be stacked in the thickness direction to make up stacked sheaves of planographic printing plates to handle them as wrapped stacked sheaves. In this case, the stacked sheaves in a wrapped state are generally put into packing boxes of corrugated fiberboard for handling.

Such packing boxes involve various management problems including the need for cost reduction, prevention of damages to coats and management of multiple product types, if any, and many parties including the present applicants have made proposals to solve these problems (e.g. Japanese Patent Application Laid-Open No. 54-12996, Japanese Patent Application Laid-Open No. 1-99976, Japanese Patent Application Laid-Open No. 1-45273, Japanese Patent Application Laid-Open No. 1-253431, Japanese Patent Application Laid-Open No. 10-16946, Japanese Patent Application Laid-Open No. 2000-95271, Japanese Patent Application Laid-Open No. 10-269456 and Japanese Patent Application Laid-Open No. 6-122469).

Of these applications, Japanese Patent Application Laid-Open No. 54-12996 discloses a proposal to fabricate a packing box by folding the edges of bottom board. Japanese Patent Application Laid-Open No. 1-99976 discloses one to have a packing device cover only the outer circumference of the stacked object. Japanese Patent Application Laid-Open No. 1-45273 discloses a packing device provided with binding strings. Japanese Patent Application Laid-Open No. 1-253431 discloses a method of manufacturing corrugated fiberboard as an external packing material.

Japanese Patent Application Laid-Open No. 10-16946 proposes a packing box provided with tubular reinforcements on the edges. Japanese Patent Application Laid-Open No. 2000-95271 proposes protective members for absorbing the energy of external forces working on sides. Japanese Patent Application Laid-Open No. 10-269456 a method of assembling a packing box by folding the edges of bottom board. Japanese Patent Application Laid-Open No. 6-122469 proposes the use of a material, not an aluminum foil or the like, permitting little permeation of moisture.

The implementation of any of these proposals is claimed to result in achievement of the intended purpose.

DISCLOSURE OF THE INVENTION

However, at the moment, none of them is found to have satisfied all the requirements of planographic printing plate packing structures. For instance, what can help reduce the cost has no preventive measure against damages to the coat, or another that also can help reduce the cost involves problems in the management of multiple product types.

More specifically, for instance, according to Japanese Patent Application Laid-Open No. 1-99976 cited above is poor in protective or buffering function against external forces, and nothing is done to prevent the coat from damages. Or according to Japanese Patent Application Laid-Open No. 10-16946, light would easily leak in through gaps in the packing box and expose the coat to that light. Or according to Japanese Patent Application Laid-Open No. 2000-95271, though the inside of the box is securely intercepted from light, the structure is complex, inviting a higher cost. It involves another problem of difficulty in breaking the bow when it is to be discarded.

Troubles with currently available planographic printing plate packing structures will be described with reference to figures. FIG. 9 and FIG. 10 show partial sections of the vicinities of edges of conventional planographic printing plate packing structures. As shown in FIG. 9 and FIG. 10, planographic printing plates 12 and coat-protecting slip-sheets 10 are alternately stacked one over the other in the thickness direction, and protective fiberboards (not shown) are further arranged over the upper face and underneath the lower face to constitute a stacked sheaf 20 of planographic printing plates 12. By then (internally) packing the stacked sheaf 20 with an inner packing sheet (not shown) and fitting in the packing structure into planographic printing plate packing boxes 2, the planographic printing plate packing structures 4.

The planographic printing plate packing boxes 2 are boxes formed by folding corrugated fiberboards. Of these, what is shown in FIG. 9 has its upper part 2A and lower part 2B stacked one over the other. Each of these upper part 2A and lower part 2B is formed by folding a corrugated fiberboard twice, and parts 2C meeting the left side of the stacked sheaf 20 are formed in a crested shape. Therefore, the left side of the stacked sheaf 20 and these parts 2C are not exactly parallel. In other words, the clearance between these parts 2C and the left side of the stacked sheaf 20 varies from C to C′, and this variation may invite instability of the stacked sheaf 20 within the box, an undesirable aspect from the viewpoint of preventing damages to the coat.

On the other hand, what is shown in FIG. 10 is a box formed by folding a corrugated fiberboard in a double-walled U shape. In this structure again, the left side of the stacked sheaf 20 and a part 2D meeting it are not exactly parallel. Therefore, the stacked sheaf 20 is apt to move within the box, and this also is an undesirable aspect from the viewpoint of preventing damages to the coat.

An object of the present invention, attempted in view of these circumstances, is to provide a planographic printing plate packing box which can prevent the coats of planographic printing plates from being damaged and can help solve problems regarding cost reduction and management adaptability to multiple product types and a planographic printing plate packing structure using the planographic printing plate packing box.

In order to achieve the object stated above, according to the invention, there is provided a planographic printing plate packing box, formed by folding one or more corrugated fiberboards, for fitting in and packing inside a stacked object of a plurality of planographic printing plates, the planographic printing plate packing box being, wherein an end side portion of the corrugated fiberboard or fiberboard being folded to so arrange side of the end side portion as to oppose a side of the stacked object, and a side of the end side portion and a side of the stacked object are at least as close to parallelism as 30 degrees.

According to the invention, as sides of the tips of the end side portions of folded fiberboards are so arranged as to oppose sides of the stacked object and the sides of the tips of the end side portions and a side of the stacked sheaf are at least as close to parallelism as 30 degrees, the movement of the stacked sheaf within the box can be readily restrained, which is an advantage from the viewpoint of preventing the coat from being damaged.

Incidentally, in the present invention, it is generally preferable for the shape of the stacked object to be rectangular. “Parallelism” according to the Japanese Industrial Standards (JIS) is supposed to what gives a sense of any plane parallel to a reference plane, or the space between mutually parallel two planes, but in the context of the present specification it means the angle one plane forms relative to the other plane.

Also according to the invention, there is provided a planographic printing plate packing box, formed by folding one or more corrugated fiberboards, for fitting in and packing inside a stacked object of planographic printing plates, the planographic printing plate packing box being, wherein an end side portion of the corrugated fiberboard or fiberboard being folded to so arrange side of the end side portion as to oppose a side of the stacked object, with a spacer member is enabled to be arranged on those out of the four sides of the stacked object that do not oppose the tip of the end side portion, and a side of the spacer member and a side of the stacked object are at least as close to parallelism as 30 degrees.

According to the invention, as sides of the tips of the end side portions of folded fiberboards are so arranged as to oppose a side of the stacked object, a spacer member is enabled to be arranged on those out of the four sides of the stacked object that do not oppose the tip of the end side portion, and a side of the spacer member and a side of the stacked object are at least as close to parallelism as 30 degrees, the movement of the stacked sheaf within the box can be readily restrained, which is an advantage from the viewpoint of preventing the coat from being damaged.

It is preferable according to the invention for two opposite sides out of the end side portions of the corrugated fiberboard to be folded.

Folding of the opposite sides in this way makes it easy to restrain the movement of the stacked sheaf within the box from both sides, which serves to further reduce the trouble of damaging the coats of planographic printing plates.

It is also preferable according to the invention for the clearance between a side of the tip of the end side and a side of the stacked object to be 10 mm or less. Also, it is preferable according to the invention for the clearance between sides of the spacer members and a side of the stacked object to be 10 mm or less. The clearance of 10 mm or in this way makes it easy to restrain the movement of the stacked sheaf within the box, which serves to further reduce the trouble of damaging the coats of planographic printing plates.

The invention further provides a planographic printing plate packing structure, wherein it packs planographic printing plates by using the planographic printing plate packing box. According to the invention, since planographic printing plates are packed by using various planographic printing plate packing boxes described above, the movement of the stacked sheaf within the box can be readily restrained, which is an advantage from the viewpoint of preventing the coat from being damaged.

As hitherto described, the present invention can provide a planographic printing plate packing box capable of keeping the coats of planographic printing plates relatively free from damages and a planographic printing plate packing structure using the planographic printing plate packing box.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a perspective view of a process of packing planographic printing plates by using a planographic printing plate packing material;

FIG. 2 shows a perspective view of the external appearance of a stacked sheaf packing structure;

FIGS. 3 A through 3D show a method of fabricating a planographic printing plate packing box according to the invention;

FIG. 4 shows a plan of the planographic printing plate packing box according to the invention;

FIG. 5 shows a section of line 5-5 in FIG. 4;

FIG. 6 is a partially enlarged view showing the vicinity of the left end of a planographic printing plate packing box in another embodiment;

FIG. 7 shows a plan of a developed state of a planographic printing plate packing box in another embodiment;

FIG. 8 is a partially enlarged view showing the vicinity of the left end of a planographic printing plate packing box in still another embodiment;

FIG. 9 is a partially enlarged view showing the vicinity of the left end of a conventional planographic printing plate packing box; and

FIG. 10 is a partially enlarged view showing the vicinity of the left end of another conventional planographic printing plate packing box.

DESCRIPTION OF SYMBOLS

10 . . . Slip-sheet (packing material for planographic printing plate), 12 . . . planographic printing plate, 16 . . . protective fiberboard, 20 . . . stacked sheaf, 22 . . . inner packing sheet, 24 . . . stacked sheaf packing structure, 30 . . . planographic printing plate packing box, 32 . . . corrugated fiberboard, S . . . spacer member

BEST MODE FOR CARRYING OUT THE INVENTION

A preferable aspect for realizing a planographic printing plate packing box and a planographic printing plate packing structure using the planographic printing plate packing box (first embodiment) will be described with reference to accompanying figures.

FIG. 1 shows a perspective view of a process of packing a planographic printing plate 12 by using an inner packing sheet 22 and slip-sheets 10. As shown in FIG. 1, planographic printing plates 12 and slip-sheets 10 for protecting the coats are alternately stacked one over the other in the thickness direction, and protective fiberboards 16 and 16 are further arranged over the upper face and underneath the lower face to constitute a stacked sheaf 20 of the planographic printing plates 12.

By then (internally) packing the stacked sheaf 20 with an inner packing sheet 22, a stacked sheaf packing structure 24 is formed. Incidentally, the protective fiberboards 16 and 16 are dispensable.

The planographic printing plate 12 fabricated by covering a thin aluminum formed in an oblong plate with a coat (a photosensitive layer if it is to be a photosensitive printing plate or a thermosensitive layer if it is a thermosensitive printing plate). The coat is subjected to plate making processes including exposure to light, development and gumming, and set onto a printing press, and characters, images or the like are printed by on the paper surface by applying ink to it.

The planographic printing plate 12 in the present embodiment is at a stage prior to necessary processing for printing (including exposure and development), and may sometimes be referred to as a blank planographic printing plate or a raw planographic printing plate.

There is no particular limitation to the specific configuration of the planographic printing plate 12 if only it is formed as described above. For instance, if it is fabricated as a planographic printing plate for laser printing by a heat mode system or a photon system, the planographic printing plate can be made usable for printing directly from digital data.

By differently selection the contents of the photosensitive layer or the thermosensitive layer of the planographic printing plate 12, the plate can be adapted to many different plate making methods. The following specific aspects, (1) through (11), are conceivable for the planographic printing plate according to the invention.

(1) An aspect in which the photosensitive layer contains an infrared absorbent, a chemical compound which generates an acid by thermal reaction and a chemical compound which forms a cross-linkage by acid.

(2) An aspect in which the photosensitive layer contains an infrared absorbent and a chemical compound which becomes alkali-soluble by acid.

(3) An aspect in which the photosensitive layer has a chemical compound which generates a radical when irradiated with a laser beam, an alkali-soluble binder, and two sub-layers including one consisting of a multifunctional monomer or prepolymer and the other being an oxygen intercepting sub-layer.

(4) An aspect in which the photosensitive layer consists of two sub-layers including a physical development nucleus layer and a silver halide emulsion layer.

(5) An aspect in which the photosensitive layer consists of three sub-layers including a polymerized sub-layer containing a multifunctional monomer and a multifunctional binder, a sub-layer containing silver halide and a reducing agent, and an oxygen intercepting sub-layer.

(6) An aspect in which the photosensitive layer consists of two sub-layers including one containing novolak resin and naphtoquinone azide and the other containing silver halide.

(7) An aspect in which the photosensitive layer contains an organic photoconductor.

(8) An aspect in which the photosensitive layer consists of two or three sub-layers including a laser beam absorbing layer which is removed by irradiation with a laser beam, an oleophilic layer and/or a hydrophilic layer.

(9) An aspect in which the photosensitive layer contains a chemical compound which absorbs energy and generates an acid, a macromolecular chemical compound which has on a side chain a functional group caused to generate sulfonic acid or carbonic acid by an acid and a chemical compound which gives energy to an acid generator by absorbing visible light.

(10) An aspect in which the photosensitive layer contains a quinone azide chemical compound and novolak resin.

(11) An aspect in which the photosensitive layer contains a chemical compound which is decomposed by light or ultraviolet rays to form a bridging structure with itself or another molecular in the layer and an alkali-soluble binder.

In particular, planographic printing plates having highly photosensitive coats which are sensitive to laser beams and thermosensitive planographic printing plates have also come into use in recent years (e.g. in modes (1) through (3) described above). For such highly sensitive planographic printing plates, by using the packing material for planographic printing plates according to the invention, the quality of the image formation faces can be securely prevented from deteriorating.

Incidentally the planographic printing plate 12 in the present embodiment (a planographic printing plate in any of modes (1) through (11) described above) may be set in a state of constituting a stacked sheaf 20 on an automatic plate making machine having an automatic plate feeding function, a so-called plate setter or the like and supplied to the plate making process.

When the planographic printing plates 12 are set on an automatic plate making machine having an automatic plate feeding function, a so-called plate setter or the like, the planographic printing plates 12 may be set without protective fiberboards 16 and in a small quantity consisting of about two each of planographic printing plates 12 and slip-sheets 10.

And as already described with reference to FIG. 1, a stacked sheaf 20 of planographic printing plates 12 are formed by alternately stacking slip-sheets 10 for protecting coats and planographic printing plates 12 one over the other in the thickness direction, and protective fiberboards 16 are further arranged over the upper face and underneath the lower face of the sheaf.

There is no particular limitation to the number of planographic printing plates 12 to constitute one stacked sheaf 20, but it can be 10 to 100 for instance with a view to the efficiency of conveyance and storage. When a stacked sheaf 20 is composed of 10 to 100 planographic printing plates 12 in this way, it is preferable to fix the planographic printing plate 12 and the protective fiberboards 16 with an adhesive tape or some other fixing device to prevent them getting out of position.

FIG. 2 shows a perspective view of the external appearance of the stacked sheaf packing structure 24. The stacked sheaf packing structure 24 is formed by internally packing the stacked sheaf 20 as described above with in prescribed positions the inner packing sheet 22 and sticking the inner packing sheet 22 with adhesive tape pieces 28, 28 . . . in prescribed positions.

The above described configuration serves to fix the inner packing sheet 22 from inadvertently expanding or coming off and thereby to securely intercept the planographic printing plate 12 from light and moisture. In this way, the stacked sheaf packing structure 24 is formed in the present embodiment by internally packing the stacked sheaf 20 with the inner packing sheet 22. The stacked sheaf packing structure 24 is further externally packed with (accommodated in) a planographic printing plate packing box according to the invention.

Next, a planographic printing plate packing box 30 according to the invention will be described in detail. The planographic printing plate packing box 30, formed by folding one or more corrugated fiberboards 32, is a packing box for fitting inside and packing a stacked sheaf packing structure 24 (a stacked body of planographic printing plates).

FIGS. 3A through 3D show a method of fabricating (assembling) the planographic printing plate packing box 30. The assembling process proceeds in the sequence charted in FIGS. 3A through 3D. FIG. 3A shows a rectangular corrugated fiberboard 32 to serve as the raw material for the planographic printing plate packing box 30.

First, as shown in FIG. 3B, discardable portions H, H . . . of the corrugated fiberboard 32 in the up and down directions and the like are cut off and folding lines (or rule marks) are formed, which are represented by thick lines in the figure. Then right and left discardable portions H, H . . . are cut off and more folding lines (thick lines in the figure) are formed as shown in FIG. 3C.

In the state shown in FIG. 3C, the folding lines enables developed parts of the planographic printing plate packing box 30 to be distinguished. Thus, a bottom board 36, a front ceiling plate 38A, a rear ceiling plate 38B, a front side plate 40A, a rear side plate 40B, a lower left side plate 42A, a lower right side plate 42B, upper left front side plate 42C, an upper right front side plate 42D, an upper left rear side plate 42E and an upper right rear side plate 42F can constitute the outer faces of a rectangular prism (packing box).

A bottom left folded portion 44A, a bottom right folded portion 44B, a top front left folded portion 46A, a top front right folded portion 46B, a top rear left folded portion 48A and a top rear right folded portion 48B can constitute the inward folded part of the rectangular prism (packing box).

Then, the bottom left folded portion 44A, the bottom right folded portion 44B, the top front left folded portion 46A, the top front right folded portion 46B, the top rear left folded portion 48A and the top rear right folded portion 48B are folded inward (upward in the figure) into a state 30′ shown in FIG. 3D. Incidentally, as it is shown in FIG. 3D, the stacked sheaf packing structure 24 is mounted on the bottom board 36.

Next, the front ceiling plate 38A and the rear ceiling plate 38B are folded inward (upward in the figure) to complete the planographic printing plate packing box 30. FIG. 4 shows a plan of the planographic printing plate packing box 30, wherein the upper face constitute the front ceiling plate 38A and the rear ceiling plate 38B.

By fabricating (assembling) the planographic printing plate packing box 30 in this way, a packing box matching the size of the product (the stacked sheaf packing structure 24) can be readily fabricated (assembled), which can help solve problems regarding cost reduction and management adaptability to multiple product types and accordingly is an advantage. Especially if a method by which a development of the planographic printing plate packing box 30 matching the size of the product is automatically designed with a computerized device to control the device to cut off the discardable portions H, H . . . and that to form folding lines (thick lines in the figure) is adopted, solution of the problems regarding cost reduction and management adaptability to multiple product types will be further facilitated.

Next, the folded structure of end side portions (shadowed portions in FIG. 3C) which are characteristic of the present invention will be described. The following description will refer to the left part of the planographic printing plate packing box 30 shown in FIGS. 3A through 3D by way of example. FIG. 5 shows a section of line 5-5 in FIG. 4 and a partially enlarged view showing the vicinity of the left end of the planographic printing plate packing box 30.

As shown in FIG. 5, an end side portion of the corrugated fiberboard is folded, and a side of the tip of this end side portion is so arranged as to oppose a side of the stacked sheaf 20 (or instead the stacked sheaf packing structure 24). More specifically, an end side portion of the rear ceiling plate 38B is folded, the upper left rear side plate 42E constitutes the left side wall, and the top rear left folded portion 48A is parallel to the rear ceiling plate 38B. And a side of an end side tip 48T of the top rear left folded portion 48A is so arranged as to oppose the upper half of a side of the stacked sheaf 20 (stacked object).

An end side portion of the bottom board 36 is folded, the lower left side plate 42A constitutes the left side wall, and the bottom left folded portion 44A is parallel to the bottom board 36. A side of an end side tip 44T of the bottom left folded portion 44A is so arranged as to oppose the lower half of a side of the stacked sheaf 20 (the stacked sheaf packing structure 24).

Further, the side 48T at the tip of an end side portion of the top rear left folded portion 48A and the upper half of a side of the stacked sheaf 20 are at least as close to parallelism as 30 degrees, and the side 44T at the tip of an end side portion of the bottom left folded portion 44A and the lower half of a side of the stacked sheaf 20 are at least as close to parallelism as 30 degrees. If the degree of parallelism between a side of the stacked sheaf 20 and any part in contact with it is satisfactory in this way, the movement of the stacked sheaf 20 within the box can be readily restrained, which is an advantage from the viewpoint of preventing the coat from being damaged.

Further, a clearance C1 between the side 48T at the tip of an end side portion of the top rear left folded portion 48A and the upper half of a side of the stacked sheaf 20 is 10 mm or less, and a clearance C2 between the side 44T at the tip of an end side portion of the bottom left folded portion 44A and the lower half of a side of the stacked sheaf 20 is 10 mm or less. If the clearance between a side of the stacked sheaf 20 and any part in contact with it is 10 mm or less, the movement of the stacked sheaf 20 within the box can be readily restrained, which serves to further reduce the trouble of damaging the coats of planographic printing plates.

Incidentally, though the left side wall formed by folding an end side portion of the rear ceiling plate 38B (the upper left rear side plate 42E) and the left side wall formed by folding an end side portion of the bottom board 36 (the lower left side plate 42A) is inclined similar to their counterparts in conventional configurations (the part 2C in FIG. 9 and the part 2D in FIG. 10) as shown in FIG. 5, these are nothing to affect the quality of the stacked sheaf 20, because they do not come into contact with the stacked sheaf 20.

Next, corrugated fiberboards 32 for in such planographic printing plate packing boxes 30 will be described. Corrugated fiberboard 32 having corrugations ranked A (strong), C, B or E (weak) under JIS Z 1516 can be used.

Regarding the layer configuration of corrugated fiberboards 32, any of triple wall corrugated fiberboards AAA (strong), double wall corrugated fiberboards AA and double faced corrugated fiberboards A (weak) under JIS Z 1516 can be used.

Regarding the type of liners of the two faces of corrugated fiberboards 32, any of AA (strong), A, B and C (weak) under JIS P 3902 or other standards can be used.

Regarding the basis weight of liners of the two faces of corrugated fiberboards 32, any in the range of 440 g/m² (strong) to 160 g/m² (weak) can be used.

Regarding the core type of corrugated fiberboards 32, any of the reinforced core A (strong), B and C (weak) under JIS P 3904 or other standards can be used.

Regarding the core the basis weight of corrugated fiberboards 32, any of 280 g/m² (strong) to 100 g/m² (weak) can be used.

Regarding alternatives to corrugated fiberboards 32, any core medium of 200 g/m² to 2000 g/m² in basis weight can be used.

Next, another embodiment (second embodiment) of the present invention will be described. Incidentally, since the present embodiment differs from the first embodiment already described substantially only in the respect that two corrugated fiberboards 32 are stacked to fabricate (assemble) a planographic printing plate packing box 130, illustration and detailed description will be omitted.

FIG. 6 is a partially enlarged view showing the vicinity of the left end of the planographic printing plate packing box 130 in the present embodiment, and corresponds to FIG. 5 for the first embodiment.

As shown in FIG. 6, end side portions of corrugated fiberboards 32 and 132 are folded, and a side each of these end side portions are so arranged as to oppose a side of the stacked sheaf 20 (stacked object). A side T1 at the tip of an end side of the upper folded portion is so arranged as to oppose the upper half of a side of the stacked sheaf 20 (stacked object). A side T2 at the tip of an end side of the lower folded portion is so arranged as to oppose the lower half of a side of the stacked sheaf 20 (stacked object).

Further, the side T1 at the tip of an end side of the upper folded portion and the upper half of a side of the stacked sheaf 20 are at least as close to parallelism as 30 degrees, and the side T2 at the tip of an end side of the lower folded portion and the lower half of the side of the stacked sheaf 20 are at least as close to parallelism as 30 degrees. If the degree of near parallelism between a side of the stacked sheaf 20 and any part in contact with it is satisfactory in this way, the movement of the stacked sheaf 20 within the box can be readily restrained, which is an advantage from the viewpoint of preventing the coat from being damaged.

Further, a clearance C3 between the side T1 at the tip of an end side portion of the upper folded portion and the upper half of a side of the stacked sheaf 20 is 10 mm or less, and a clearance C4 between the side T2 at the tip of an end side portion of the lower folded portion and the lower half of the side of the stacked sheaf 20 is 10 mm or less. If the clearance between a side of the stacked sheaf 20 and any part in contact with it is 10 mm or less, the movement of the stacked sheaf 20 within the box can be readily restrained, which serves to further reduce the trouble of damaging the coats of planographic printing plates.

Next, still another embodiment (third embodiment) of the present invention will be described. In the third embodiment, end side portions of corrugated fiberboards are folded, and a side each of the tips of these end side portions are so arranged as to oppose a side of the stacked object, with spacer members are enabled to be arranged on those out of the four sides of the stacked object that do not oppose the tips of the end side portions. Regarding the present embodiment, too, as in the case of the second embodiment, illustration and detailed description of the fabricating (assembling) method will be omitted.

FIG. 7 shows an interim state of fabrication (assembly) in the present embodiment corresponding to FIG. 3D of the first embodiment. FIG. 8 is a partially enlarged view showing the vicinity of the left end of a planographic printing plate packing box 40 in the present embodiment.

As shown in FIG. 7, the stacked sheaf packing structure 24 is mounted in the central part (bottom board) of a corrugated fiberboard 2, and spacer members S and S are so arranged as to be in tight contact with the two sides of the stacked sheaf packing structure 24. These spacer members S are rod-shaped members having a rectangular section, about as thick as the stacked sheaf packing structure 24.

Therefore, as shown in FIG. 8, the right sides of the spacer members S and the left side of the stacked sheaf 20 (the stacked sheaf packing structure 24) are at least as close to parallelism as 30 degrees. If the degree of near parallelism between a side of the stacked sheaf 20 and the spacer members S in contact with it is satisfactory in this way, the movement of the stacked sheaf 20 within the box can be readily restrained, which is an advantage from the viewpoint of preventing the coat from being damaged.

A clearance C5 between sides of the spacer members S and the side of the stacked sheaf 20 (the stacked sheaf packing structure 24) is 10 mm or less (substantially zero). If the clearance between the part in contact with the side of the stacked sheaf 20 is 10 mm or less (substantially zero), the movement of the stacked sheaf 20 within the box can be readily restrained, which serves to further reduce the trouble of damaging the coats of planographic printing plates.

Incidentally, though parallelism between the left side walls of the spacer members S and the part 2D opposing them is poor in the planographic printing plate packing box 40 of FIG. 8 as in the earlier described conventional configuration shown in FIG. 10, this is nothing to affect the function to restrain the movement of the stacked sheaf 20 in the box.

As hitherto described, the present invention can provide a planographic printing plate packing box which prevents the coats of planographic printing plates 12 from being damaged and can help solve problems regarding cost reduction and management adaptability to multiple product types, and a planographic printing plate packing structure using the planographic printing plate packing box.

So far, embodiments of the invention regarding a planographic printing plate packing box and a planographic printing plate packing structure using the planographic printing plate packing box have been described, but the invention is not limited to these embodiments but can also be implemented in various other modes.

For instance, while corrugated fiberboards are used as the material for planographic printing plate packing in the foregoing embodiments, other packing materials, such as thick paper sheets functioning similarly to corrugated fiberboards, can as well be used with similar effects to those of the above-described embodiments. 

1. A planographic printing plate packing box, formed by folding one or more corrugated fiberboards, for fitting in and packing inside a stacked object of a plurality of planographic printing plates, the planographic printing plate packing box being, wherein an end side portion of the corrugated fiberboard or fiberboard being folded to so arrange side of the end side portion as to oppose a side of the stacked object, and a side of the end side portion and a side of the stacked object are at least as close to parallelism as 30 degrees.
 2. A planographic printing plate packing box, formed by folding one or more corrugated fiberboards, for fitting in and packing inside a stacked object of planographic printing plates, the planographic printing plate packing box being, wherein an end side portion of the corrugated fiberboard or fiberboard being folded to so arrange side of the end side portion as to oppose a side of the stacked object, with a spacer member is enabled to be arranged on those out of the four sides of the stacked object that do not oppose the tip of the end side portion, and a side of the spacer member and a side of the stacked object are at least as close to parallelism as 30 degrees.
 3. The planographic printing plate packing box according to claim 1, wherein two opposite sides out of the end side portions of the corrugated fiberboard are folded.
 4. The planographic printing plate packing box according to claim 1, wherein the clearance between the side of the tip of the end side of the corrugated fiberboard and a side of the stacked object is 10 mm or less.
 5. The planographic printing plate packing box according to claim 2, wherein the clearance between the side of the spacer member and a side of the stacked object is 10 mm or less.
 6. A planographic printing plate packing structure, wherein the planographic printing plate packaging structure packs planographic printing plates by using the planographic printing plate packing box according to claim
 1. 7. The planographic printing plate packing box according to claim 2, wherein two opposite sides out of the end side portions of the corrugated fiberboard are folded.
 8. The planographic printing plate packing box according to claim 3, wherein the clearance between the side of the tip of the end side of the corrugated fiberboard and a side of the stacked object is 10 mm or less.
 9. The planographic printing plate packing box according to claim 7, wherein the clearance between the side of the tip of the end side of the corrugated fiberboard and a side of the stacked object is 10 mm or less.
 10. A planographic printing plate packing structure, wherein the planographic printing plate packaging structure packs planographic printing plates by using the planographic printing plate packing box according to claim
 2. 11. The planographic printing plate packing box according to claim 3, wherein the clearance between the side of the spacer member and a side of the stacked object is 10 mm or less.
 12. The planographic printing plate packing box according to claim 7, wherein the clearance between the side of the spacer member and a side of the stacked object is 10 mm or less. 